Forging machine



Aug. 7, 1934. H. MULLER 1,969,317

FORGING MACHINE Filed Oct. 12. 1929 3 Sheets-Sheet 1 INVEN TOR.

Han; Miizzez" A TTORNE Y.

1934' H. MULLER 1,969,317

FORGING' MACHINE Filed Oct. 12, 1929 3 SheetsSheet 2 Fig.3

' S w -\v 12 IN VEN TOR:

14472 J McZZZcT;

A TTORNE Y.

H. MULLER FORGING MACHINE Aug. 7, 1934.

Filed Oct. 12. 1929 5 Sheets-Sheet 5 INVENTOR. Han: M

By if 7 ATTORNEY.

Patented Aug. 7, 1934 'PATENT OFFICE FORGING MACHINE Hans Miiller, Hagen, Germany Application October 12,

1929, Serial No. 399,256

In Germany October 16, 1928 7 Claims. (01. 76-9) The present invention relates to a stretching machine for forging unwieldy tools, such as the prongs of forks for handling hay and stones. Such stretching machines with hammer-slides gliding in revolving or fixed guides, upon which hammer slides bars may be forged into round or angular cross-section are known. In these machines, however, the hammers have been placed very deeply into the interior of the machine body, with the result that it is impossible to introduce unwieldy work-pieces, such as the prongs of forks for handling hay or stones, into the machine.

There are, furthermore, stretching machines with fixed hammer-guides, in which, for the pur-.- pose of an improved accessibility of the forging tools, the latter have been installed in the frontplate of the'machine, in connection with which the striking forces are transferred in a forward direction by means of a lever from a roller-gear or suchlike. But even the accessibility of the forging jaws attained with the aid of this arrangement is not sufficient for the purpose of insuring a sufllcient capacity. These machines, moreover, favour the formation of an undesirable bur at the edges when forging long conical prongs. With these machines it is impossible to install the forging jaws directly within the levers, whereby the desired accessibility would be rendered possible, because they are too far removed from the forging centre. The cause of this excessive distance of the levers from the forging centre will be found in the disposition of the gear producing the striking forces, which, in view of the reversal of the direction of movement of the levers directs the striking forces radially in an outward direction, for the purpose of obtaining at the front hammer slides which are directed towards the centre. It has, furthermore, been impossible to forge long, conical prongs with the aid of these machines without the formation of bur at the edges. When forging, it is, as a matter of fact, necessary to hold the work-piece accurately in the striking centre of the hammers, because otherwise the narrow forging jaws do not hit said work-pieces properly. This is however, an easy matter with bars of constant cross-section, by passing them through a properly fitting hole-guide, whereas with conical bars, such as the prongs of forks, it is not possible to employ a hole-guide.

The present invention is characterized in that the levers actuated by a roller striking-gear or suchlike have been so disposed that they terminate immediately at the point of the striking tools, so that the latter may be attached to the ends of the levers proper; and furthermore, that with an arrangement of this description a device has been connected which prevents. the formation of bur at the edges when forging long, 69 conical prongs.

In order to attain the desired immediate at-.- tachment of the forging jaws to the ends of the levers so as to' ensure maximum accessibility, the arrangement of the levers in relation to the gear 5 producing the striking force has been improved, so that the levers are disposed within a rollergear or suchlike striking in an inward direction, in connection with which the levers, however, in order to prevent a reversal of the striking 7 direction, are of the one-armed type.

Furthermore, a device has been installed, with the aid of which it will be possible to avoid the formation of bur in connection with conical forging, which device simultaneously acts as an accurate guide for conical bars also, inasmuch as this guide in regard to its width is changed simultaneously with the adjustment of the striking width of the hammers, this being necessary for conical forging.

In the drawings which represent an example of the invention,

Fig. 1 is a cross-section of the whole of the machine along the line 11 of Fig. 2,

Fig. 2, on the right, a section along the line 35 2-2 of Fig. 1 and one the left, half a front view of the machine;

Fig. 3 is an enlarged representation of the forging jaws and arrangement of the keys, whereas Fig. 4 is a front view thereof.

Fig. 5 is a modification of the invention,

Fig. 6 shows forging jaws of ordinary design applied to the levers of applicants machine,

Fig. 7 is a section along the line 6--6 of Fig. 5.

A roller striking-gear consisting, in a known manner, of an outer body 1, several rollers 2 contained in a cage, and an interior body 3 is arranged so that the driving slides 4 produce striking forces directed inwardly. The slots of the driving slides 4 enclose levers 5, at their backward ends by fulcrum-pins or roller journals 6, so that they are acting as one-armed levers thus transferring thestriking forces taken up, upon the forward ends of the levers to which the striking tools '7 have been attached. The levers 5 are made to rest snugly against the slides 4 by means of the springs 8 guided in the interior of the body 3. The levers are so dimensioned that their ends with the forging jaws 7 no tween the, forging jaws.

project some distance beyond the straight guide body 3.

For the purpose of forging fork-prongs with the aid of these machines it is, however, further necessary that the striking width of the forging jaws may be'gradually changed in order to produce the conical form of the prongs.v With the present invention the adjustment of the striking width is effected by displacing a wedge 9 by ing centre, the present invention provides in place of a fixed hole-guide, adjustable guidecalipers 10 which are installed behind, and be- The adjusting device for the calipers 10, e. g. a wedge 11 capable of being displaced, and which also may be made to consist of one or more parts, is connected with the adjusting device of the striking lever 5 viz.

the wedge 9, consisting of one or a plurality of parts, so that the adjustment is therefore properly effected jointly.

The drawings represent a machine, in which the interior body 3 with the hammer leverguides is at rest or'stationary and the outer body 1 is made to revolve with the roller-cage. In accordance with the invention machines may be constructed, in which the interior body revolves with the hammer-guides and the outer body is stationary.

When forging fork-prongs and suchlike upon the machinedescribed previously in relation to Figs. 14, it will always be necessary to bend the various flaps of the work-piece apart in order that they may pass between the hammers without hindering the adjoining flaps. This bending apart may be avoided by introducing the work-piece in between the hammers of the machine, so that the adjoining flaps are accommodated in the diagonal gaps between the hammers. But in that case the forging action of the hammers upon the flaps to be forged is faulty, because the cross-section of the flap is rectangular in most cases, i. e. the width of the material very considerably exceeds its thickness,

The hammers will consequently hit the flap-surfaces obliquely, glide oif, and chop up the ma-- terial, without being able to forge it properly. By means of such an arrangement only square cross-sections would be properly struck and forged. In order, however, to render the forging of rectangular cross-sections possible, they are, in accordance with the invention, placed in normal position to the diagonal position of the hammers, i. e. they are turned by 45 against the surface of the material. This may now be effected by a: special working operation under a suitable press in a bending swage prior to forging, or else in the forging machine proper, for which purpose the hammer jaws will be so formed that they bring about the twist of the flaps by 45 immediately themselves.

In conjunction with this working operation, however, a considerable counter effect will make itself felt in the opposite sense of twist, which should have to be taken up by the tongs and the hand of the smith, which is a matter of considerable difficulty. In view of the fact that when forging these work pieces it concerns roughs of a regular shape, which, apart from forks, is particularly favorable when forging rake prongs. The present invention is modified so that the counter effect against the twisting of the prong flaps by 45 is produced by guiding the neighboring prongs in suitable sleeves, in connection with which the central guide of the prongs to be forged is effected between pairs of hammers.

The hammer guides in Fig. 5 have been placed in the 45 position, for the purpose of securing for the guides of the work-piece the more convenient horizontal position. In the horizontal gaps of the hammers the cross-sections a, b, c of the flaps or prongs of the work-piece have been inserted. The flap a, Figs. 5 and 7 is guided in a guide sleeve 14, the finished prong c in a guide sleeve 15, while the flap b is made to rest freely between the hammers.

If this flap b were to be struck in its original position, as specially represented in Fig. 6,

by hammer jaws of the ordinary design, it would be badly chopped by the latter. It is for that reason that the hammer jaws shown in Figs. 5 and 7 on either side of the half-round forging mould proper are provided with broad faces 16, which cause the flap to be twisted by 45 and. obviate the possibility of chopping up. The original position of the cross-section of the flap, illustrated by dotted lines in Fig. 5, is immediately changed by the first blow of the hammer and made to assume the 45 position drawn in full lines, with the result that the forging may be eifected in the normal proper manner. In connection herewith, the guiding of the workpiece accurately in the axial centre between the hammer jaws 7 is insured by the sleeves 14 and 15.

I claim:'

1. In a forging machine, the combination of a plurality of levers oppositely arranged in pairs about a common axis, a pivotal connection for one end of each of said levers, forging tools having flat surfaces adjacent each side of the forging surface and carried by the free ends of said levers-recessed members positioned on each side of said forging tools at a forty-five degree angle to the flat surfaces thereof, said members being constructed and arranged to position the rough blank of a rake, pitch fork, or the like by receiving the prongs thereof adjacent the prong being formed, and means for impelling said levers together.

2. In a forging'machine, a frame, a plurality of forging levers oppositely arranged in pairs about a'common axis, means to support one end of each lever on the frame with the free ends of the levers projecting beyond the frame, forging tools carried by said free ends, a cylindrical guide body carried by the frame and slotted to receive said levers, slides mounted in said slots and having cam ends protruding normally through the slots, a revolving ring surrounding said guide body and slides, rollers interposed between said guide body and revolving ring and rolling on said'ring, and a cage holding said rollers spaced around the ring.

3. In a forging machine, a frame, a plurality of forging levers oppositely arranged in pairs about a common axis, means to support one end of each lever on the frame with the free ends of the levers projecting beyond the frame, forging tools carried by said free ends, a cylindrical guide body carried by the frame and slotted to receive said levers, slides mounted in said slots and having cam "ends protruding normally through the slots, a revolving ring surrounding said guide body and slides, rollers interposed between said guide body and revolving ring and rolling on said ring, a cage holding said rollers spaced around the ring, and means carried by the frame to position a blank to be forged between said jaws.

4. In a forging machine, a frame, a plurality of forging levers oppositely arranged in pairs about a common axis, means to pivotally support one end of each lever on the frame with the free ends of the levers projecting beyond the frame, forging tools carried by said free ends, a cylindrical guide .body carried by the frame and slotted to receive said levers, slides mounted in said slots and having cam ends protruding normally through the slots, a revolving ring surrounding said guide body and slides, rollers interposed between said guide body and revolving ring and rolling on said ring, a cage holding said rollers spaced around the ring, and means for radially adjusting said pivot means, said means being operable during oscillation of said levers.

5. In a forging machine, a frame, a plurality of forging levers oppositely arranged in pairs about a common axis, means to pivqtally support one end of each lever on the frame with the free ends of the levers projecting beyond the frame, forging, tools carried by said free ends, a cylindrical guide body carried by the frame and slotted to receive said levers, slides mounted in said slots and having cam ends protruding normally through the slots, a revolving ring surrounding said guide body and slides, rollers interposed between said guide body and revolving ring and rolling on said ring, a cage holding said rollers spaced around the ring, means carried by the frame to position a blank to be forged between said jaws, and means for radially adjusting said pivot means, said means being operable during oscillation of said levers.

6. In a forging machine, the combination of a plurality of levers oppositely arranged in pairs about a common axis, a pivotal connection for one end of each of said levers, forging tools carried by the free ends of said levers, means for impelling each pair of said levers together, and recessed members positioned on each side of the said forging tools, said members being constructed and arranged to position the rough blank of a rake, pitch fork or the like, by receiving the prongs thereof adjacent the prong being forked.

7. In a forging machine, the combination of a plurality of levers oppositely arranged in pairs about a common axis, a pivotal connection for one end of each of said levers, forging tools carried by the free ends of said levers, means for impelling each pair of said levers together, and recessed members positioned on each side of the said forging tools, said members being constructed and arranged to position the rough blank of a rake, pitch fork or the like, by receiving the prongs thereof adjacent the prong being forged, said recessed members being positioned on each side of said forging tools at a forty-five degree angle thereto.

5 HANS MiiunR. 

